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Stock Option And Benefit Plans (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Millions					12 Months Ended
	Aug. 09, 2021	Jul. 23, 2020	Jul. 27, 2019	Jul. 27, 2018	Jul. 03, 2021	Jun. 27, 2020	Jun. 29, 2019	Jul. 26, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		155,000	175,000	161,250
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other than Option, Nonvested, Intrinsic Value		$ 6.94		$ 8.17				$ 4.93
Grant date fair value		$ 2.32	$ 1.23	$ 2.27
Stock-based compensation expense					$ 0.2	$ 0.3	$ 0.4
Unrecognized share based compensation expense					$ 0.3
Share Based Expense Recognition - Weighted-average period					1 year 9 months 21 days
Company contributions to 401K					$ 0.9	$ 0.8	$ 0.9
July 23, 2020 SAR Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding SARs					150,000
July 26, 2019 SAR Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding SARs					140,000
July 27, 2018 SAR Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding SARs					116,250
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	165,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other than Option, Nonvested, Intrinsic Value	$ 7.17
Grant date fair value	$ 2.73